1. Technical Field
The disclosure relates to a method and a system of image reconstruction as well as a method and a system of image construction.
2. Related Art
In accordance with the medical researches on risk factors for cancers, e.g., for breast cancer, the strongest known risk factor is high breast density (breast composition). The breast density may be categorized into six levels: 0, <10% (less than 10% glandular tissue), 10% to 25%, 25% to 50%, 50% to 75%, and >75%. The denser the breast, the more likely to develop breast cancer.
Imaging on patients (including human beings and animals), e.g., taking photographs of body regions where malignant lesions may occur, help a doctor diagnose cancer. For instance, a doctor may evaluate and determine whether a woman has breast cancer through mammography. According to statistical results, ductal carcinoma in situ (DCIS) of the breast cancer discovered by mammography accounts for approximately 20% of all kinds of breast cancers, and 90% of the stage-0 DCIS of the breast cancer is diagnosed through micro-calcifications. Calcifications are often scattered throughout the mammary glands. In the breast with high density, the calcifications and the mammary glands are indicative of high X-ray absorption and are frequently overlapped. Hence, the calcifications may not be easily distinguished from the mammary glands through the two-dimensional X-ray images obtained by applying the existing mammography, which may mislead the diagnosis of the doctor.
To precisely observe the internal conditions of patients, a computed tomography (CT) scan technique may be applied. For instance, the CT scan technique may be performed to learn the internal structure of human breasts. According to the CT scan, plural two-dimensional X-ray images of the breast are taken in various directions. A three-dimensional image is then generated from the two-dimensional X-ray images through computer simulation. Although the CT scan allows the doctor to learn the internal conditions of human breasts in an accurate manner, the high radiation in form of X-rays used for taking the two-dimensional X-ray images in the CT scan process may lead to high possibility of cancer.